Despite being locked in a tight Senate race with the governor, incumbent Republican U.S. Sen. Kelly Ayotte has refused to directly engage Hassan on the issue, saying it's too important an issue to politicize. But a National Republican Senate Committee ad has targeted Hassan, and poll numbers suggest that the crisis of addiction is a top issue in the race.

Hassan called the ad disgusting and harmful, and Ayotte has denounced it. But the Hassan campaign isn't letting Ayotte off the hook. A new online ad ties the senator to the national ad.

"They're at it again," the Hassan ad says. "Kelly Ayotte's special interest allies from Washington using the opioid crisis to attack Maggie Hassan."

The one-minute ad includes testimonials on Hassan's behalf.

The governor has called the crisis of addiction the No. 1 issue facing the state, and in the latest WMUR Granite State Poll, 43 percent of Granite Staters agreed.

"More than half of the voters in this state say that they know somebody who has abused heroin, and more than half think that the state ought to be doing more about spending money on this," University of New Hampshire pollster Andy Smith said.

Smith said Ayotte might be playing it too safe on the issue, and as a result, she might now be playing from behind on it.

"We say that making things political is a bad thing, but elections are about politics," Smith said. "Elections are about public choices for policy, which is why this should be a political issue in this campaign."

The Ayotte campaign declined to comment on Hassan's ad, saying that Ayotte's position on the issue is clear and unchanged.